Combine the like terms to create an equivalent expression: ${r+(-5r)}$
Combine the ${r}$ terms: r + ( − 5 r ) = = ( 1 − 5 ) r − 4 r { \begin{eqnarray} {r} +(- 5{r}) &=& (1 - 5){r} \\ &=& -4{r} \end{eqnarray}} The simplified expression is $-4r$.